Add QT extension

extensions/desktop/qt-framework/Makefile

@@ -0,0 +1,34 @@
+#!/usr/bin/make -f
+
+SRC_DIR ?= .
+
+DATA_DIR             := $(DESTDIR)/data-dir
+BIN_DIR              := $(DESTDIR)/snap/command-chain
+LIB_DIR              := $(DESTDIR)/lib
+DEST_LAUNCHER        := desktop-launch
+LOCALE_GENERATOR     := locale-gen
+DEST_CONFIGURE_HOOK  := hooks-configure-desktop
+
+build: $(DEST_LAUNCHER) $(DEST_CONFIGURE_HOOK)
+
+clean:
+	rm -f $(DEST_LAUNCHER)
+	rm -f $(DEST_CONFIGURE_HOOK)
+	rm -f $(BINDTEXTDOMAIN)
+
+$(DEST_LAUNCHER):
+	@cat $(SRC_DIR)/init > $(DEST_LAUNCHER)
+  # tail -n +2 to remove the shebang
+	@tail -n +2 $(SRC_DIR)/desktop-exports | sed -e "s/%PLATFORM_PLUG%/$${PLATFORM_PLUG:?}/" >> $(DEST_LAUNCHER)
+	@tail -n +2 $(SRC_DIR)/launcher-specific >> $(DEST_LAUNCHER)
+	@tail -n +2 $(SRC_DIR)/mark-and-exec >> $(DEST_LAUNCHER)
+
+$(DEST_CONFIGURE_HOOK):
+	@cat $(SRC_DIR)/fonts > $(DEST_CONFIGURE_HOOK)
+
+install: $(DEST_LAUNCHER) $(DEST_CONFIGURE_HOOK)
+	install -d $(DATA_DIR)
+	install -d $(DATA_DIR)/kf5
+	install -D -m755 $(DEST_LAUNCHER) "$(BIN_DIR)"/$(DEST_LAUNCHER)
+	install -D -m755 $(LOCALE_GENERATOR) "$(BIN_DIR)"/$(LOCALE_GENERATOR)
+	install -D -m755 $(DEST_CONFIGURE_HOOK) "$(BIN_DIR)"/$(DEST_CONFIGURE_HOOK)

extensions/desktop/qt-framework/desktop-exports

@@ -0,0 +1 @@
+../common/desktop-exports

extensions/desktop/qt-framework/fonts

@@ -0,0 +1 @@
+../common/fonts

extensions/desktop/qt-framework/init

@@ -0,0 +1 @@
+../common/init

extensions/desktop/qt-framework/launcher-specific

@@ -0,0 +1,63 @@
+#!/bin/bash
+###################################
+# QT launcher specific part #
+###################################
+
+# Add paths for games
+append_dir PATH "$SNAP/usr/games"
+append_dir PATH "$SNAP_DESKTOP_RUNTIME/usr/games"
+
+# Qt Libs
+prepend_dir LD_LIBRARY_PATH "$SNAP_DESKTOP_RUNTIME/usr/lib/$ARCH/qt6-5/libs"
+
+# Add QT_PLUGIN_PATH (Qt Modules).
+append_dir QT_PLUGIN_PATH "$SNAP/usr/lib/$ARCH/qt6-5`/plugins"
+append_dir QT_PLUGIN_PATH "$SNAP/usr/lib/$ARCH"
+append_dir QT_PLUGIN_PATH "$SNAP_DESKTOP_RUNTIME/usr/lib/$ARCH/qt6-5/plugins"
+append_dir QT_PLUGIN_PATH "$SNAP_DESKTOP_RUNTIME/usr/lib/$ARCH/"
+# And QML2_IMPORT_PATH (Qt Modules).
+append_dir QML2_IMPORT_PATH "$SNAP/usr/lib/$ARCH/qt6-5/qml"
+append_dir QML2_IMPORT_PATH "$SNAP/lib/$ARCH"
+append_dir QML2_IMPORT_PATH "$SNAP_DESKTOP_RUNTIME/usr/lib/$ARCH/qt6-5/qml"
+append_dir QML2_IMPORT_PATH "$SNAP_DESKTOP_RUNTIME/lib/$ARCH"
+
+# Fix locating the QtWebEngineProcess executable
+export QTWEBENGINEPROCESS_PATH="$SNAP_DESKTOP_RUNTIME/usr/lib/$ARCH/qt6-5/libexec/QtWebEngineProcess"
+
+# Removes Qt warning: Could not find a location
+# of the system Compose files
+export QTCOMPOSE="$SNAP_DESKTOP_RUNTIME/usr/share/X11/locale"
+export QT_XKB_CONFIG_ROOT="/usr/share/X11/xkb"
+
+# Add path to VLC plugins
+export VLC_PLUGIN_PATH="$SNAP_DESKTOP_RUNTIME/usr/lib/x86_64-linux-gnu/vlc/plugins"
+
+# Ensure QtChooser behaves.
+export QTCHOOSER_NO_GLOBAL_DIR=1
+export QT_SELECT=5
+# qtchooser hardcodes reference paths, we'll need to rewrite them properly
+ensure_dir_exists "$XDG_CONFIG_HOME/qtchooser"
+echo "$SNAP/usr/lib/qt6-5/bin" > "$XDG_CONFIG_HOME/qtchooser/6.conf"
+echo "$SNAP/usr/lib/$ARCH" >> "$XDG_CONFIG_HOME/qtchooser/6.conf"
+echo "$SNAP/usr/lib/qt6-5/bin" > "$XDG_CONFIG_HOME/qtchooser/default.conf"
+echo "$SNAP/usr/lib/$ARCH" >> "$XDG_CONFIG_HOME/qtchooser/default.conf"
+
+# This relies on qtbase patch
+# 0001-let-qlibraryinfo-fall-back-to-locate-qt.conf-via-XDG.patch
+# to make QLibraryInfo look in XDG_* locations for qt.conf. The paths configured
+# here are applied to everything that uses QLibraryInfo as final fallback and
+# has no XDG_* fallback before that. Currently the most interesting offender
+# is QtWebEngine which will not work unless the Data path is correctly set.
+cat << EOF > "$XDG_CONFIG_HOME/qt.conf"
+[Paths]
+Data = $SNAP_DESKTOP_RUNTIME/usr/share/qt6-5/
+Translations = $SNAP_DESKTOP_RUNTIME/usr/share/qt6-5/translations
+EOF
+
+if [ -e "$SNAP_DESKTOP_RUNTIME/usr/share/i18n" ]; then
+    export I18NPATH="$SNAP_DESKTOP_RUNTIME/usr/share/i18n"
+    locpath="$XDG_DATA_HOME/locale"
+    ensure_dir_exists "$locpath"
+    export LOCPATH="$locpath:/usr/lib/locale"
+    LC_ALL=C.UTF-8 async_exec "$SNAP/snap/command-chain/locale-gen"
+fi

extensions/desktop/qt-framework/locale-gen

@@ -0,0 +1,62 @@
+#!/usr/bin/perl
+
+use strict;
+
+sub uniq
+{
+    my %seen;
+    grep !$seen{$_}++, @_;
+}
+
+# TODO support for KDE's in-app language switch feature.
+sub get_languages
+{
+    # Initialize with sane defaults.
+    my @found_languages = ($ENV{'LANG'} or 'C.UTF-8');
+
+    # Go through LC_.
+    foreach (sort keys %ENV)
+    {
+        if (substr($_, 0, length("LC_")) eq "LC_")
+        {
+            push(@found_languages, $ENV{$_});
+        }
+    }
+    # And finally LANGUAGE, but normalize it.
+    if (my $language = $ENV{'LANGUAGE'})
+    {
+        foreach (split(':', $language))
+        {
+            push(@found_languages, "$_.UTF-8");
+        }
+    }
+
+    # Remove duplicates before returning.
+    @found_languages = uniq(@found_languages);
+
+    return @found_languages
+}
+
+my $env_locpath = $ENV{'LOCPATH'} or die "LOCPATH must be set";
+my @locpaths = split(/:/, $env_locpath);
+
+foreach my $lang (get_languages())
+{
+    my $found = 0;
+    foreach my $locpath (@locpaths)
+    {
+        my $loc_target = "$locpath/$lang";
+        if (-e $loc_target)
+        {
+            $found = 1;
+            last;
+        }
+    }
+    next if $found;
+    my $target = "@locpaths[0]/$lang";
+
+    # localedef will exit !0 for unknown reasons, even when everything was
+    # generated fine.
+    my ($locale, $encoding) = split(/\./, $lang);
+    system('localedef', '-i', $locale, '-f', $encoding, $target);
+}

extensions/desktop/qt-framework/mark-and-exec

@@ -0,0 +1 @@
+../common/mark-and-exec

schema/snapcraft.json

@@ -914,6 +914,7 @@
                                     "gnome-3-34",
                                     "gnome-3-38",
                                     "kde-neon",
+                                    "qt-framework",
                                     "ros1-noetic",
                                     "ros2-foxy"
                                 ]

snapcraft/extensions/qt_framework.py

@@ -0,0 +1,212 @@
+# -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
+#
+# Copyright 2022 Canonical Ltd.
+#           2023 Jarred Wilson <jarred.wilson@canonical.com>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 3 as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+"""Generic QT Framework extension to support core22 and onwards."""
+import dataclasses
+import functools
+from typing import Any, Dict, List, Optional, Tuple
+
+from overrides import overrides
+
+from .extension import Extension, get_extensions_data_dir, prepend_to_env
+
+_SDK_SNAP = {"core22": "qt-framework-sdk"}
+
+
+@dataclasses.dataclass
+class ExtensionInfo:
+    """Content/SDK build information."""
+
+    cmake_args: str
+
+
+@dataclasses.dataclass
+class QTSnaps:
+    """A structure of QT related snaps."""
+
+    sdk: str
+    content: str
+    builtin: bool = True
+
+
+class QTFramework(Extension):
+    r"""The QT Framework extension.
+
+    This extension makes it easy to assemble QT based applications.
+
+    It configures each application with the following plugs:
+
+    \b
+    - Common Icon Themes.
+    - Common Sound Themes.
+    - The QT Frameworks runtime libraries and utilities.
+
+    For easier desktop integration, it also configures each application
+    entry with these additional plugs:
+
+    \b
+    - desktop (https://snapcraft.io/docs/desktop-interface)
+    - desktop-legacy (https://snapcraft.io/docs/desktop-legacy-interface)
+    - opengl (https://snapcraft.io/docs/opengl-interface)
+    - wayland (https://snapcraft.io/docs/wayland-interface)
+    - x11 (https://snapcraft.io/docs/x11-interface)
+    """
+
+    @staticmethod
+    @overrides
+    def get_supported_bases() -> Tuple[str, ...]:
+        return ("core22",)
+
+    @staticmethod
+    @overrides
+    def get_supported_confinement() -> Tuple[str, ...]:
+        return "strict", "devmode"
+
+    @staticmethod
+    @overrides
+    def is_experimental(base: Optional[str]) -> bool:
+        return False
+
+    @overrides
+    def get_app_snippet(self) -> Dict[str, Any]:
+        return {
+            "command-chain": ["snap/command-chain/desktop-launch"],
+            "plugs": ["desktop", "desktop-legacy", "opengl", "wayland", "x11"],
+        }
+
+    @functools.cached_property
+    def qt_snaps(self) -> QTSnaps:
+        """Return the QT related snaps to use to construct the environment."""
+        base = self.yaml_data["base"]
+        sdk_snap = _SDK_SNAP[base]
+
+        build_snaps: List[str] = []
+        for part in self.yaml_data["parts"].values():
+            build_snaps.extend(part.get("build-snaps", []))
+
+        builtin = True
+
+        for snap in build_snaps:
+            if sdk_snap == snap.split('/')[0]:
+                builtin = False
+                break
+
+        # The same except the trailing -sd
+        content = sdk_snap[:-4]
+
+        return QTSnaps(sdk=sdk_snap, content=content, builtin=builtin)
+
+    @functools.cached_property
+    def ext_info(self) -> ExtensionInfo:
+        """Return the extension info cmake_args, provider, content, build_snaps."""
+        cmake_args = "-DCMAKE_FIND_ROOT_PATH=/snap/" + self.qt_snaps.sdk + "/current"
+
+        return ExtensionInfo(cmake_args=cmake_args)
+
+    @overrides
+    def get_root_snippet(self) -> Dict[str, Any]:
+        platform_snap = self.qt_snaps.content
+        content_snap = self.qt_snaps.content + "-all"
+
+        return {
+            "assumes": ["snapd2.43"],  # for 'snapctl is-connected'
+            "compression": "lzo",
+            "plugs": {
+                "desktop": {"mount-host-font-cache": False},
+                "icon-themes": {
+                    "interface": "content",
+                    "target": "$SNAP/data-dir/icons",
+                    "default-provider": "gtk-common-themes",
+                },
+                "sound-themes": {
+                    "interface": "content",
+                    "target": "$SNAP/data-dir/sounds",
+                    "default-provider": "gtk-common-themes",
+                },
+                platform_snap: {
+                    "content": content_snap,
+                    "interface": "content",
+                    "default-provider": platform_snap,
+                    "target": "$SNAP/qt-framework",
+                },
+            },
+            "environment": {"SNAP_DESKTOP_RUNTIME": "$SNAP/qt-framework"},
+            "hooks": {
+                "configure": {
+                    "plugs": ["desktop"],
+                    "command-chain": ["snap/command-chain/hooks-configure-desktop"],
+                }
+            },
+            "layout": {"/usr/share/X11": {"symlink": "$SNAP/qt-framework/usr/share/X11"}},
+        }
+
+    @overrides
+    def get_part_snippet(self) -> Dict[str, Any]:
+        sdk_snap = self.qt_snaps.sdk
+        cmake_args = self.ext_info.cmake_args
+
+        return {
+            "build-environment": [
+                {
+                    "PATH": prepend_to_env(
+                        "PATH", [f"/snap/{sdk_snap}/current/usr/bin"]
+                    ),
+                },
+                {
+                    "XDG_DATA_DIRS": prepend_to_env(
+                        "XDG_DATA_DIRS",
+                        [
+                            f"$CRAFT_STAGE/usr/share:/snap/{sdk_snap}/current/usr/share",
+                            "/usr/share",
+                        ],
+                    ),
+                },
+                {
+                    "SNAPCRAFT_CMAKE_ARGS": prepend_to_env(
+                        "SNAPCRAFT_CMAKE_ARGS",
+                        [
+                            cmake_args,
+                        ],
+                    ),
+                },
+            ],
+        }
+
+    @overrides
+    def get_parts_snippet(self) -> Dict[str, Any]:
+        # We can change this to the lightweight command-chain when
+        # the content snap includes the desktop-launch from
+        # https://github.com/snapcore/snapcraft-desktop-integration
+        source = get_extensions_data_dir() / "desktop" / "qt-framework"
+
+        if self.qt_snaps.builtin:
+            return {
+                "qt-framework/sdk": {
+                    "source": str(source),
+                    "plugin": "make",
+                    "make-parameters": [f"PLATFORM_PLUG={self.qt_snaps.content}"],
+                    "build-snaps": [self.qt_snaps.sdk],
+                },
+            }
+
+        return {
+            "qt-framework/sdk": {
+                "source": str(source),
+                "plugin": "make",
+                "make-parameters": [f"PLATFORM_PLUG={self.qt_snaps.content}"],
+            },
+        }